Poreko, I've had this very same problem in the past. You get the error concerning the verification of CTP2 if you have the game loaded twice on your computer (ie, once in your "C" Drive and again in your "D" Drive).
I got this same error because I have two operating systems on my computer (Win ME and Win2000). I originally installed CTP2 while I was in WinME. Then later, I started my computer in Win2000, tried to play CTP2 but was told I had to load it - so I did. But when I tried to load the patch (while in Win2000), I got the error that it couldn't verify the location/version of CTP2. Basically, the patch was confused because I had CTP2 loaded in WinME (C drive) and in Win2000 (D drive).
The way to solve this is to uninstall CTP2 from your computer, then look in all of your hard drives to make sure that there isn't a CTP2 loaded again. When you find the second load of CTP2, you will need to manually delete the Activion/CTP2 folder and all files. Restart your computer. Reload CTP2. Install the patch. You should have no further problems.
Hope this helps
[This message has been edited by Wittlich (edited April 18, 2001).]